Author Topic: Asthma Season - pollution masks question again, sorry!  (Read 1567 times)

Asthma Season - pollution masks question again, sorry!
« on: 05 November, 2019, 03:08:53 pm »
It's my asthma season again. I've not cycle commuted for some time but planning on getting back into it. So masks come up again.

I know most people struggle with them and don't find them that good. Also car passengers have 4x the pollution.  However I'm still thinking it's worth trying again.

Anyone try a mask? It so which one? Thinking cheaper cambridge mask company disposable or more expensive respro cinquo with powa extreme replaceable filters. Totobobo are cheap at £25 and you can replace three filters but heard they're even more difficult to breathe through.

So anyone try them? Views on each brand and model gratefully received. I understand there's issues with them I've read about them but little about people actually experiencing them for themselves. Mostly there's professional writers/ reviewers which seems slightly missing in real life use info.

hellymedic

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Re: Asthma Season - pollution masks question again, sorry!
« Reply #1 on: 05 November, 2019, 03:30:01 pm »
I still can't see how ANY mask can filter 3-5 litres per second without bypassing...

... but I never got on with masks I tried so I'm not the one to ask.

Re: Asthma Season - pollution masks question again, sorry!
« Reply #2 on: 05 November, 2019, 03:42:21 pm »
Does volume of breath increase much with exercise? I know it must increase in frequency but actual breath volume each intake?

Kim

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Re: Asthma Season - pollution masks question again, sorry!
« Reply #3 on: 05 November, 2019, 03:57:12 pm »
Other than the throughput, I thought the main issue is that most masks are designed for dust, chemicals etc, not the small particulates in vehicle exhaust. 

Basil

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Re: Asthma Season - pollution masks question again, sorry!
« Reply #4 on: 05 November, 2019, 04:03:28 pm »
I was once told by a hospital doctor that in order to filter out the really dangerous particles, you'd need a mesh so fine that you'd have difficulty breathing through it.  To get round this you could increase the surface area of the filter, but unfortunately it would need to be so large you wouldn't be able to see round it.

I'm not sure how serious he was being.
Admission.  I'm actually not that fussed about cake.

Re: Asthma Season - pollution masks question again, sorry!
« Reply #5 on: 05 November, 2019, 04:17:38 pm »
PM 0.3, 2.5 and 10 are the three categories of concern in urban/ traffic pollution. Depending on the rating of the mask most of this can be filtered out with a good fitting mask.

The key thing is to look for N99, P99, FFP3 / P3 ideally with 2CV afterwards. These filter out 99% of all PM 0.3 to PM 10 particulates. That's down to 0.3 microns. That's covering diesel sourced particulates that can pass into your blood.

Truth is you're unlikely to get a good fit without training and mask fitting. Totobobo seem to understand that by the way they are promoting a way to customise their masks for a better fit. Complete with a way to test its effectiveness. Iirc when correctly fitted you can see moisture build up in the clear mask. A kind of moisture tide line all around your mouth and nose area. Totobobo masks ship with N90 filters iirc. They filter only 90% of those particulates they do supply replacement filters for N95 and N99 ratings (95% and 99% of particulates).

You have to read the small print I reckon.

I did find a link about determining pollution levels. It's about distance you can see through it. No haze = no need for a mask,  1 to 2km visibility you need it and the filters probably only lasts a couple of months.  Something like that anyway.  More pollution the more often the filters need replacing. Totobobo are white and you replace when it's too dark. Others less clear. Some are simply based on fixed times based on hours use for different pollution levels.

Re: Asthma Season - pollution masks question again, sorry!
« Reply #6 on: 05 November, 2019, 04:22:38 pm »
I was once told by a hospital doctor that in order to filter out the really dangerous particles, you'd need a mesh so fine that you'd have difficulty breathing through it.  To get round this you could increase the surface area of the filter, but unfortunately it would need to be so large you wouldn't be able to see round it.

I'm not sure how serious he was being.

He mustn't have been serious or he was ignorant about PPE. Either is possible.

Yes breathing isn't as easy but even with respro type masks people cope. I've once seen someone with a heavy duty mask. The ones covering nose and mouth with two protruding filter housings. They are heavy duty ones.

It's a choice I reckon. If going without one is worse than wearing one you'll make that decision.

hellymedic

  • Just do it!
Re: Asthma Season - pollution masks question again, sorry!
« Reply #7 on: 05 November, 2019, 04:28:10 pm »
Both Tidal VOLUME and respiratory RATE increase with exercise.
A lot.
https://www.bbc.co.uk/bitesize/guides/z3xq6fr/revision/2

I still don't see how a fine filter can treat large volumes without HUGELY increasing the work of breathing. I would be interested in input from anaesthetic and respiratory colleagues.

rr

Re: Asthma Season - pollution masks question again, sorry!
« Reply #8 on: 05 November, 2019, 04:40:24 pm »
Masks are certainly available that are capable of removing a large proportion of the fine particles, BUT they need to fit you properly so that they seal around your face.
If they don't they are useless. Different makes and models fit different people and they need to be done up really tightly. You also need to be clean shaven.
For use at work a face fit test is expected to demonstrate than that mask can provide that person with adequate protection.
Breathing through a properly sealed P3 mask is hard work and if you are going to exert yourself or wear it for an extended period powered respirators are needed.
Your friendly, local asbestos removal supplies company may be able to help.

http://www.hse.gov.uk/respiratory-protective-equipment/

Sent from my moto x4 using Tapatalk

Kim

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Re: Asthma Season - pollution masks question again, sorry!
« Reply #9 on: 05 November, 2019, 04:42:53 pm »
I still don't see how a fine filter can treat large volumes without HUGELY increasing the work of breathing. I would be interested in input from anaesthetic and respiratory colleagues.

OTOH, a fit asthmatic is probably quite good at breathing, and it'll only be a fraction of the work of cycling.  I suspect armed forces people with experience of soldiering in NBC gear, or people who do physical work in hazardous environments would have more relevant experience than the medics, who tend to be treating sick people at rest.

I can't help feeling that a powered respirator or a powered bike would be needed to make this really practical, unless the only requirement is that it be a bit faster than walking.

hellymedic

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Re: Asthma Season - pollution masks question again, sorry!
« Reply #10 on: 05 November, 2019, 06:02:40 pm »
I am (thankfully) not asthmatic. I have wheezed once in my lifetime so I have scant experience of how it really feels.

I'm told it feels like breathing through a straw. This would fit with my experience with a mask. It was a great relief to remove the mask and I really would not wish that constrained breathing sensation on anyone.

I don't really think a powered respirator is a practical prospect for a cycle commuter but someone might put me straight.